Automatic bbake



" UNITED sTAilEs PATENT oFFroE.

JOHN IVILKINSON, OF BALTIMORE, MARYLAND.

AUTOMATIC BRAKE.

Speccation of Letters Patent No. 31,047, dated January 1, 1861.

To all whom 'it may concern.'

Be it known that I, Jol-IN VILI'iINsoN, of Baltimore, in the State ofMaryland, have invented an Automatic Brake for Carriages; and thefollowing is a full, clear, and exact description of the principle orcharacter which distinguishes it from all other things before known, andof the usual manner of making, modifying, and using the same, referencebeing had to the accompanying draw ing, of which- Figure 1 is aperspective view of the carriage body and brake. Fig. 2 a longitudinalmiddle sect-ion of the same.

My invention is an automatic brake for 1carriages described andrepresented as folows:

Many attempts have hitherto been essayed to make an automatic brake forcarriages, that is to say a brake which once started into action shallcontinue independently of the driver to operate with varying degrees offorce according to the necessities of the case. It is obvious that allbrakes which are operated through the pole 0f the carriage are notstrictly speaking automatic for they are iny directly operated bythedriver and are subject to the caprices of the horses. In my inventionthe brake is applied by the relative position of the front and hindwheels, that is, whenever the carriage is on a descending grade, or thehind wheels are higher than the front ones, the brake isinstantlyapplied by the rocking of the front axle. After the brake is in actionit operates itself and to an extent commensurate with the necessities ofthe case and in such manner that the greater the weight or pressure ofthe carriage in descending a hill the greater the pressure o n. thebrakes, and will operate upon the carriage as well without as withhorses. The pressure of the brakes is effected by the vibration orrocking of the axle in the following manner. From the main bolster athere is suspended a subbolster b by means of the drop cheeks 0 whichare firmly fixed to bolster a, these cheeks being suitably braced byrods Z and e. The subbolster rocks or vibrates upon suitable bearings inthe cheek posts c. The middle of the subbolster is enlarged in acircular form f to make the fifth wheel bearing for the axle g. Arisingfrom the center of f is a stout pillar h and to the upper part of thispillar is attached the brake rod z' which operates the brakes y'. Theupper part of this pillar enters a recess.

team the bolt k is to be pushed by the driver.

in front of the pillar h which prevents the action of the brake. Thisbolt k is supported by two lug pieces m attached to the` bolster L andplays back and forth under the action of the lever a with which it isconnected. The pillar h may be considered as a prolongation of the kinglbolt of the carriage or that bolt which holds the axle to the bolsternot necessarily shown here.

From the foregoing description it will be seen that if the bolt c, iswithdrawn from Y before the pillar z. while the carriage is descending ahill the forward pressure will cause the sub-bolster to rock on itsbearings and with it the axle g and the pillar h being thus thrownforwardwill draw upon the brake rod z', and the heavier the load or thegreaterv the inclination of the road the greater will be the pullexerted upon the brake rod and thus we have what may strictly be termedan automatic brake.

As an auxiliary brake I connect with the brake rod z' a chain p which isattached to the hand-brake rod 7 which is made to rock on suitablebearings s connected with the bolster a, by the movements of hand levert attached to the outer end of this rod; this lever being held inposition by the usual means of a notched bar u which is attached to posto. This post serves also for the bearings of the lever a which operatesto call into action the automatic brake, both levers being accessible tothe driver from the seat w.

The auxiliary brake can be operated in conjunction with the automaticbrake or independently at pleasure and it is obvious that the automaticbrake is relieved from action as soon as the draft of the horses is feltupon the tongue z causing the axle to rock backward and bring the pillarla into a vertical position, when the bolt c may be returned to itsplace. The red lines in Fig. 2 indicate the position of the parts whilethe automatic brake is in action.

The same principle of using the rocking motion of the axle may beapplied to the rear axle Without Changing the character of my invention.

I do not claim operating the brake by the i Weight of the load, exceptwhen the same is done by the vibratory or rocking motion of the axle asabove set forth; therefore What I claim as my improvement is- Operatingcarriage brakes by the vibration or rocking of the axle substantially in10 the manner and upon the principles herein set forth; and for thispurpose I claim the sub-bolster Z) and its pillar /L combined With themain bolster' a as set forth.

JOHN WILKINSON. Vitnesses CHAS. Gr. PAGE, WM. H. HARRISON.

